Air cleaning apparatus



March 11, 1941. H. c. LAMBERT ETAL AIR CLEANING APPARATUS Filed Aug. 5, 1937 2 Sheets-Sheet 1 Henry 6. Lam/56m 570m? A". Gar/may March 11,1941.

H. c. LAMBERT ETAL AIR CLEANING APPARATUS Filed Aug. 5, 1937 2 Sheets-Sheet 2 Henry C 4007660 tented Mar. ll, 194i NlTED STATES PATENT oFFicE AIR CLEANING APPARATUS Application August 5, 1937, Serial No. 157,509

1 Claim.

This invention relates to air cleaning apparatus ior use particularly in'connection with spray booths, to remove from the exhaust air, paint, lacquer and other foreign matter entrained therein as a result of spraying operations.

it is found in practice that exhaust air moving at a high velocity gathers the overspray from the spray gun much more efficiently than with a slow-: moving column of air, and also that the cleaning action is more eflicient in the former case than in the latter.

The object of the invention is to so act on the air in its passage through the outlet throat and the expansion and eliminating chambers as to cause a material acceleration of the air current by a restriction and immediate expansion thereoi, and to cause the air during such action to pass through a liquid spray, such as water with a saponiiying agent therein, whereby a thorough, rapid and efilcient cleaning of the air is effected.

A further object of the invention is the provision of means in the rear of a spray booth, whereby liquid used to clean the exhaust air is captured after the cleaning operation and caused to how ever and wash down the inner rear wall surface of the spray booth and eniciently and economically prevent the accumulation thereon of paint or other material being sprayed. This means also provides a liquid curtain through which the exhaust air from the booth passes.

Uther objects and advantages of the invention wilt be apparent from the following detailed deacriptlon thereof, and from the accompanying drawings, in whicht le 1 is a side elevation of an apparatus embodying the invention, with parts broken away; Fig. 2 is an enlarged vertical section of a part thereof, and Fig. 3 is a front elevation of the apparatus, with parts broken away.

Referring to the drawings, I designates a room or comrtment containing the air to be cleaned and which, in the present instance, comprises part oi a booth commonly used in paint sprayworh.

at the rear side of the booth or compartment i is a housing t in which the cleaning of the exhaust air irom said compartment takes place.

in the bottom portion of the housing 2 is an open top tank 3 containing a cleaning liquid t which may preferably but not necessarily conatitute water with a saponifying agent therein. iibove the tank 3 and in the rear portion of the housing is an exhaust throat passage 5 opening at its top into an expansion chamber Ii in the top portion of which are located a series of eliminator or baffle plates i forming a plurality of zigzag upwardly extending passages B. The air, after passing through the eliminator passages 8, enters a blower chamber ill at the top of the housing and is then discharged by the blower II. 5 The action of this blower is such as to create a strong draft from the booth and through the cleaning apparatus.

Between the tank 3 and floor plate H of the expansion chamber 5 in advance of the throat l passage is a space it which is open at its front side to the booth chamber 41 and forms a part thereof.

The throat passage 5 is of rectangular form in cross-section, being narrow in one direction and broad in the other, and communicates at its lower end with the space 13, and between such point of communication and the expansion chamber 6 it has a slot-like Venturi restriction formed by the opposed upwardly extending inwardly inclined plates i5 and i6 which, immediately above the point of greatest restriction of the passage, diverge outwardly on an incline relative to the passage to permit expansion of the air in its upward passage through the throat. The cleaning liquid is discharged in spray-form into the restricted portion of the throat passage from a plurality of nozzles it on a pipe i9 which has connection through a pump 20 with the liquid in the tank 3, so that liquid may be drawn from the tank and forcefully discharged from the nozzles into the throat passage. The nozzles it are disposed within the throat passage 5 above the Venturi restriction thereof and have a conical spray discharge downwardly in the passage, the spray cones being adapted to overlap each other and also to overlap the upper restricted edge portions of the plates I15 and it, so that all portions of the restricted portion of the throat passage are covered by the spray. This causes all of the air in its passage through the throat to pass through the liquid spray and to carry a considerable portion of the spray therewith. In practice, the spray nozzles are placed about six inches apart throughout the length of the portion of the pipe it within the throat passage.

The wall between the throat b and chamber i3 is formed by two spaced parallel plates Iii, the outer one of which has a plain outer side exposed to the chamber i3 while the inner plate carries at its inner side the passage restricting plate it. The plates ii are connected at their lower edges and near their upper edges by webs H the upper of such webs cooperating with the upper end portions of the inner and outer plates 

